North Pole may be open enough for reinforced shipping by mid-century

Northwest Passage, Russian coastal routes will admit open water vessels.

By mid-century, open water vessels (blue) could navigate above both Russia and Canada, while reinforced vessels could go straight across the pole.

With Arctic sea ice reaching record lows, people have begun to explore routes through Canada's Northwest Passage and the Northern Sea Route above the coast of Russia. These routes have the potential to significantly shorten transit times between Asia and both Europe and North America, reducing shipping costs and fostering international trade.

At the moment there is little guarantee that the routes will be open in any given year, which is enough to keep shippers from taking full advantage of the shrinking ice. Having a better grip on when the ice is likely to recede enough to allow shipping would greatly aid planning. So two geographers at UCLA took a series of climate models and ran the numbers for two emissions scenarios. Based on their estimates, lightly reinforced vessels could cross directly over the pole by mid-century, and regular vessels could traverse both the Russian and Canadian routes.

One of the problems here is that climate models have consistently underestimated how quickly the ice would be vanishing each summer. The authors therefore ran the full collection from the Coupled Model Intercomparison Project and selected the five models that did the best with historic data. They then added in two additional models that have detailed, realistic representation of sea ice and the physics associated with it. This ensemble of models was then run using two different Intergovernmental Panel on Climate Change (IPCC) emissions scenarios, one on the low end of current trends and one on the high end.

These models were used to estimate the extent and thickness of ice in September, when levels in the Arctic tend to be at their lowest. The authors then considered the ability of two different classes of ships to navigate the Arctic Ocean: current open water vessels that are used for global trade and a class called PC6. The PC6 vessels are built to withstand transit through first-year ice (ice that froze during the previous winter) and are currently used primarily for trade in special areas like the Baltic Sea. (You can read much more about the PC6 specs in this document.)

In the immediate future, out to 2015, not a lot changes; the only viable route is the Northern Sea Route along the Russian coast. But the dynamics of that route change. For one, it becomes open more frequently, as often as 70 percent in some models. And while open water vessels still have to hug the coast, the PC6 ships are often able to take a more direct route across the Arctic, saving time and avoiding some potential navigational hazards.

By mid-century (technically 2040 to 2059), however, things shift dramatically. There's about a 95 percent chance that the Northern Sea Route will be open in a given year, and open water vessels will no longer be limited to hugging the coast. At the same time, the Northwest passage opens up, going from having a 25 percent chance of being open to about 60 percent by mid-century. When it's open, most of the open water traffic from North America would do best by using that route; PC6 ships from North America can effectively use that route every year.

The big difference is in the area north of Russia. During many years, this area opens up enough so that open water vessels can take increasingly direct routes across the Arctic ocean, in some cases travelling close to the pole itself. Meanwhile, the reinforced PC6 ships can shoot directly across the pole itself pretty much every September. In this scenario, these ships can take a nearly direct route from Europe to Asia.

The authors note that merely having a navigable ocean isn't enough to make a trade route viable; services and infrastructure, including escorts and insurance, can raise the costs. Meanwhile, the two major canals (Suez and Panama) could adjust their fees in response. On the other side of the equation, the climate models (as noted above) have consistently underestimated the significance of the changes that are occurring in the Arctic. That means that some of these routes may open even sooner, giving us more experience and infrastructure in place by mid-century.